You would think that people with a history of being discriminated against in the workplace might give those whom they resemble a break. But a growing body of research confirms exactly the opposite: women are just as likely as men to show sexism toward women in hiring practices, salaries and professional mentorship. One study even found that people of both genders would forgo thousands of dollars in salary to have a male boss.

Overt displays of sexism of the bottom-pinching variety are largely passé in the American workplace. What remains, unfortunately, is a set of subtler and more ingrained cognitive biases deeply rooted in our evolutionary and cultural past. Getting rid of them will require an honest reckoning with the inalienable fact that humans are primed to make implicit errors in perception and even good people who actively eschew bias may nonetheless harbor subtle yet damaging stereotypes of which they are unaware.

In one of the latest studies, a psychology experiment published in the Proceedings of the National Academy of Sciences, senior science faculty across the U.S. were presented with identical résumés for a lab-manager job (a position that can often lead to graduate study) that differed only in the gender of the hypothetical applicant. The résumé raters were statistically more likely to rate the male candidate higher on competence and hirability and were also more likely to offer the male candidate a bigger salary and greater professional mentorship. By contrast, the hypothetical female applicants were rated more likable but less hirable. Female scientists were just as likely to favor male candidates as potential hires as male scientists were.

There are countless examples of bias against women by both sexes in nonscience fields, including, famously, the increase in women who were hired for orchestras when musicians auditioned behind a blind screen. It’s hard to imagine why this kind of cognitive bias persists in the 21st century, especially when the achievement gaps between males and females are closing rapidly and women now comprise the majority of college and graduate students nationwide.

But this only seems puzzling because we tend to think that bias is an evil word, tainted with ugly -isms and the deliberate diminishing of certain kinds of people. Current research is showing that all human beings have unconscious cognitive biases — what Harvard professor Mahzarin Banaji calls “mind bugs.” These biases may have been adaptive thousands of years ago, when people lived in small, homogeneous communities and in-group favoritism or snap judgments might have made the difference between life or death. But they are problematic in our global 21st century world.

Those cognitive shortcuts gave us the ability to make rapid decisions. And sometimes using them makes sense: murders are overwhelmingly more likely to be committed by young men than elderly grandmothers. The problem is that our minds are also capable of making profound errors that, in the case of Trayvon Martin, can even cost lives.

The pervasiveness of cognitive bias is depressing. It’s more palatable to think of sexism or racism or ageism as a symptom of a few rotten apples than as a fundamental human trait. But if we’re all doing it, even to ourselves, how on earth can we move beyond the stereotypes? If we want to eliminate the perception that women are less competent than men for certain jobs held by both sexes, it’s not enough to hire more women for traditionally male-dominated jobs.

There are two ways to respond to pervasive, often unconscious bias. First, we could develop better metrics for evaluating human beings that can help reduce human error. Yes, sophisticated algorithims for decisionmaking can be problematic. The use of technical data to make human decisions may come at a moral or social cost that isn’t worth paying. (Mandatory sentencing laws are one such example.) Flying on autopilot may indeed reduce accidents, but few people want to board a flight with an empty cockpit.

We must also be more intentional about recognizing unconscious stereotypes. People who score high in cognitive bias on online tests measuring implicit associations — the tendency to pair negative words with black people more quickly than with white people, for example — often express anger, shame and denial at the findings, particularly when they are 180 degrees at odds with their stated beliefs. (This author was shocked to discover an unconscious bias favoring old people, despite a lifetime of working with children and young adults!) Unfortunately, these defensive emotions are unlikely to rise to the surface, making it hard to learn from the findings.

A more fundamental problem is that cognitive bias is rooted not only in our primitive past but also in our contemporary culture. We can’t be surprised by unconscious stereotypes about women when we still embrace a culture suffused with highly sexualized, frivolous and demeaning portrayals of women in everything from popular movies to recent congressional debates.

Biases don’t appear out of thin air; they can diminish and even disappear over time. No serious person thinks anymore that women’s brains are incapable of complex thoughts, a once commonplace notion accepted even by Darwin. In other words, there’s hope that we can change. We may not eradicate the mind bugs, but we can control them until, like roaches, they flee when we turn on the lights.